Missing Data Imputation for Supervised Learning
This work addresses missing data issues for machine learning practitioners, but it is incremental as it compares existing methods on benchmark datasets.
The paper tackles the problem of missing categorical data in supervised classification by comparing imputation methods, showing that imputation can increase predictive accuracy under missing-data perturbation, achieving state-of-the-art results on the Adult dataset with k-NN imputation.
Missing data imputation can help improve the performance of prediction models in situations where missing data hide useful information. This paper compares methods for imputing missing categorical data for supervised classification tasks. We experiment on two machine learning benchmark datasets with missing categorical data, comparing classifiers trained on non-imputed (i.e., one-hot encoded) or imputed data with different levels of additional missing-data perturbation. We show imputation methods can increase predictive accuracy in the presence of missing-data perturbation, which can actually improve prediction accuracy by regularizing the classifier. We achieve the state-of-the-art on the Adult dataset with missing-data perturbation and k-nearest-neighbors (k-NN) imputation.